Beam type adjustable ballastless track structure and construction method

Abstract

This application provides a beam-type adjustable ballastless track structure and construction method, relating to the field of railway track structure technology. The track structure includes: a precast track slab with stiffening ribs extending longitudinally along its upper surface and limiting holes at both longitudinal ends; a support, located between two adjacent precast track slabs, comprising a bottom pad for supporting the bottom surface of the precast track slab ends, a limiting boss protruding upwards into the limiting holes, and a longitudinal baffle located between the longitudinal end faces of adjacent track slabs, all three integrally cast; and a three-dimensional elastic buffer assembly, including an elastic buffer pad for the limiting holes, an elastic buffer pad for the slab ends, and an elastic pad for the bottom of the slab, used to physically isolate the precast track slab from the concrete entity of the support. This application, through an innovative beam-type load-bearing system and a full-interface physical isolation and buffer structure, achieves a wide range of independent adjustment in the longitudinal, lateral, and vertical directions of the track structure, and significantly simplifies construction and maintenance procedures such as slab replacement.

Description

Technical Field

[0001] This application relates to the field of railway track technology, and in particular to a beam-type adjustable ballastless track structure and construction method. Background Technology

[0002] Ballastless track structures are commonly used in high-speed railways and urban rail transit due to their good smoothness, convenient construction, and low maintenance workload. However, my country has a vast territory and long railway lines. In complex geological areas such as active fault zones or water-rich sandy and gravelly areas, the subgrades of the track structure, including roadbeds, bridges, and tunnels, face significant risks of arching or subsidence. Ballastless track structures may arch or subside along with these subgrades, causing the track structure's geometry to deviate from its normal position. This results in decreased track smoothness, requiring trains to reduce speed when passing, increasing safety hazards, and in severe cases, potentially leading to track interruptions with significant impact.

[0003] When the subgrade foundation deforms, traditional ballastless track structures are mainly adjusted using fasteners. However, due to the limited adjustment range of the track fasteners, special methods such as lifting and correction or dismantling and reconstruction of the ballastless track are required for repair. Currently, these methods are complex, extremely costly, and have low maintenance efficiency. Therefore, there is a need to invent an adjustable ballastless track structure to meet the demands of railway lines for large-scale track structure adjustments.

[0004] Currently, several patents related to adjustable track structures have been published in the field of railway ballastless track. Chinese patent CN119711264B discloses a beam-type ballastless track with steel guard plates. This track structure requires significant construction and adjustment work for the same track length, and the limiting structure affects the track clearance, making it poorly adaptable to small-radius shield tunnels in urban rail transit and difficult to achieve drainage on both sides. Chinese patent CN108560330B discloses a secondary-cast, upgradeable, universal track bed and its construction method. This ballastless track has a multi-layered structure with complex interlayers and relatively many weak points. Chinese patent CN119392541B discloses a slab-type ballastless track adaptable to foundation deformation and its adjustment method. This ballastless track structure also suffers from problems such as complex interlayers and a large construction workload. Summary of the Invention

[0005] To address the issues of insufficient adjustability and high maintenance difficulty in traditional ballastless tracks, this application provides a beam-type adjustable ballastless track structure and construction method.

[0006] Firstly, this application provides a beam-type adjustable ballastless track structure, which adopts the following technical solution: A beam-type adjustable ballastless track structure includes: The precast track slab has stiffening ribs extending longitudinally along its upper surface, and limiting holes are provided at both longitudinal ends of the precast track slab. The support, located between two adjacent precast track slabs, includes a bottom pad for supporting the bottom surface of the end of the precast track slab, a limiting boss protruding upward into the limiting hole, and a longitudinal stop located between the longitudinal end faces of the two adjacent precast track slabs; and A three-dimensional resilient buffer assembly includes components for physically isolating the concrete body of the precast track slab from the support: The elastic buffer pad for the limiting hole is located at the interface between the precast track slab and the limiting boss. An elastic buffer pad layer is provided between the ends of two adjacent precast track slabs; An elastic pad is placed between the precast track slab and the bottom pad layer.

[0007] Furthermore, the limiting protrusion and the longitudinal baffle intersect each other perpendicularly and are arranged symmetrically in a cross shape on the bottom pad of the plate, and the three are integrally cast reinforced concrete structures.

[0008] Furthermore, the limiting hole elastic buffer pad layer, the plate end elastic buffer pad layer, and the plate bottom elastic pad are all provided with anchoring ribs on the side facing the precast track plate, and the anchoring ribs are integrally formed on the precast track plate.

[0009] Furthermore, the precast track slab is provided with an observation hole that extends vertically from its upper surface to its bottom surface. The observation hole is covered by a detachable observation hole cover plate, which is connected to the precast track slab through a sleeve and bolts embedded in the precast track slab.

[0010] Furthermore, the upper surface of the precast track slab is also provided with longitudinally spaced track support platforms, and fastener insulating sleeves are pre-embedded in the track support platforms; The number of stiffening ribs is two or four, and the multiple stiffening ribs are arranged in parallel on one side or both sides of the rail support platform.

[0011] Furthermore, the limiting hole is located at the center of the width of the prefabricated track slab, and the shape of the limiting hole is a rectangle with chamfers; Lifting sleeves are pre-embedded along the transverse sides of the precast track slab.

[0012] Furthermore, a support reinforcement cage is embedded in the support, and connecting reinforcement bars or portal reinforcement bars are provided at the bottom of the support. The support is anchored to the lower foundation through the connecting reinforcement bars or portal reinforcement bars.

[0013] Furthermore, the support is a cast-in-place support formed by on-site casting; Alternatively, the support may be a prefabricated support manufactured in a factory, and the beam-type adjustable ballastless track structure may also include a cast-in-place leveling layer disposed between the prefabricated support and the lower foundation.

[0014] Furthermore, the precast support has multiple grouting holes through the bottom plate pad layer for pouring the cast-in-place leveling layer.

[0015] Secondly, this application provides a construction method for a beam-type adjustable ballastless track, based on the aforementioned beam-type adjustable ballastless track structure.

[0016] Includes the following steps: S1. Pre-embed or implant connecting steel bars at the positions corresponding to the supports in the lower foundation; S2. Arrange the support reinforcement cage at the support location; S3. Transport the prefabricated track slab, which is integrally molded with the three-way elastic buffer components, to the site and perform rough laying and positioning on the underlying foundation; S4. Use the lifting sleeves on both sides of the precast track slab to install fine-tuning tools to fine-tune and fix the precast track slab; S5. Install a support mold between two adjacent precast track slabs. The support mold includes a slab transverse mold and a slab bottom pad mold. The slab bottom pad mold is installed and adjusted vertically downward through the observation hole in the middle of the precast track slab, and then a support steel cage is placed in the support mold. S6. Concrete is poured into the support mold in one go after positioning, so that the bottom pad layer of the slab, the limiting boss and the longitudinal baffle are integrally formed with the support reinforcement cage to form a cast-in-place support; S7. Maintain and remove the support molds to complete the track structure laying.

[0017] Alternatively, it may include the following steps: S1. Pre-embed or implant connecting steel bars at the positions corresponding to the supports in the lower foundation; S2. Precast supports are selected, and the precast supports manufactured in the factory are transported to the construction site for rough laying, layout, fine adjustment and fixing; S3. Install and fix the leveling layer mold between the precast support and the lower foundation; S4. Self-compacting concrete or high-strength mortar is injected through the grouting holes set on the bottom pad of the precast support to ensure that the cast-in-place leveling layer is densely grouted. S5. Curing of the cast-in-place leveling layer; demolding after the strength meets the requirements. S6. Transport the prefabricated track slab, which is integrally formed with the three-way elastic buffer component, to the construction site and perform fine-tuning and installation directly on the prefabricated support that has been constructed. S7. Finally, install the rails and fasteners on the track slab, measure the track structure, and complete the track structure laying.

[0018] And / or, when it is necessary to replace the prefabricated track slab, the following steps are included: Keep the original lower foundation and the aforementioned supports intact, and lift and remove the old precast track slab to be replaced as a whole. The new prefabricated track slab, which is integrally formed with the aforementioned three-way elastic buffer components, is hoisted and positioned above the original support; By casting resin material or inserting a pad of matching thickness between the contact interface of the support and the three-way elastic buffer component of the new precast track slab, the new precast track slab and the support are tightly and firmly connected.

[0019] Furthermore, when the lower foundation deforms and adjustments to the track structure are required: By utilizing the physical isolation between the precast track slab and the support, the geometric position of the precast track slab in the longitudinal, transverse and vertical directions can be independently adjusted by adding or replacing pads of different thicknesses at the locations of the elastic buffer pads at the limiting holes, the elastic buffer pads at the ends of the slabs, or the elastic pads at the bottom of the slabs.

[0020] In summary, this application includes at least one of the following beneficial technical effects: 1. This application abandons the traditional full-support mode of ballastless track slabs and innovatively adopts a beam-type force system supported by supports at both ends. By setting two or more stiffening ribs on the track slab, the bending bearing capacity of the track slab is improved, the amount of concrete poured on site is greatly reduced, and the construction efficiency and overall economy of the track structure are improved. 2. The stiffening ribs installed along the entire length of the track slab in this application significantly improve the bending capacity of the cross section, perfectly matching the mechanical requirements of the beam structure, and can meet the dynamic load bearing requirements of high-speed trains without the need for full support at the bottom of the slab; on the other hand, they integrate the anti-derailment guard function, which simplifies the structure and greatly improves the safety redundancy of train operation compared to the traditional track additional guard rail solution. 3. This application adopts an integrated cast-in-place structure of limiting boss + longitudinal baffle + bottom pad layer, which realizes the longitudinal and transverse bidirectional limiting of the track slab, with better limiting stiffness and structural stability. At the same time, it can also achieve overpass through the bottom pad layer, perfectly adapting to the construction and installation needs of curved sections. 4. This application completely breaks through the bottleneck of traditional ballastless tracks, which can only achieve small-range vertical height adjustment by relying on fasteners. Through buffer / height adjustment pads at the ends, bottom, and limiting holes of the track, the longitudinal, transverse, and vertical geometric positions of the track structure are fully adjustable. When the foundation settles, the bridge creeps, or the structure deforms during operation, adjustments can be completed simply by adding or replacing the corresponding pads, without removing any concrete main structure, making the operation convenient and efficient. The buffer pads can be prefabricated and pre-applied in the factory, and integrated with the track slab. They are anchored by ribs extending into the concrete of the track slab, solving the industry pain points of traditional ballastless track buffer pads being prone to gaps, slippage, and detachment, and significantly improving the service life and long-term structural stability of the buffer system. 5. This application adopts a simplified process of "precast slab rough laying - fine adjustment and positioning - integrated cast-in-place support", which eliminates the need for complex processes such as large-area casting of traditional ballastless track base slabs, laying of isolation layers, and separate cast-in-place casting of bosses; the mold of the bottom pad layer can be easily installed and adjusted through the observation hole in the middle of the track slab, which solves the pain points of insufficient construction space and high operation difficulty of traditional slab bottom construction, greatly shortens the on-site construction cycle, and reduces labor and machinery costs; 6. Compared with the industry pain points of traditional ballastless track replacement, which requires large-area chiseling of the base and limiting bosses, resulting in long track closure time and large amount of work, this application only requires lifting the track slab to be replaced. There is no need to damage the support and the substructure. By replacing the buffer pad layer of different specifications or the cast-in-place resin material, the new slab can be installed in close contact with the support. The replacement operation can be completed quickly within the railway operation window, which greatly reduces the interference of operation and maintenance on the line operation. 7. The through-hole in the center of the track slab in this application allows for convenient cleaning of dirt and inspection of the slab bottom during operation. The cover plate of the observation hole can also serve as an emergency passage for the track, while providing working space for daily inspections, solving the pain points of difficult defect inspection and insufficient maintenance space in traditional ballastless tracks. Moreover, the setting of the observation hole in the center of the track slab not only reduces the structural weight, but also effectively reduces the temperature gradient effect of the track slab, optimizes the stress and deformation of the track slab under temperature load, reduces the generation of temperature cracks, and further improves the long-term durability of the track structure.

[0021] 8. This application integrates multiple functions such as structural load-bearing, longitudinal and lateral limiting, three-way height adjustment, train anti-derailment, and convenient operation and maintenance into one. Compared with the traditional ballastless track scheme that requires additional components such as guard rails and height adjustment devices, the structure is more streamlined, the functions are more comprehensive, the track clearance is smaller, and the drainage method is more flexible. It can be adapted to line scenarios with different speed levels and different offline working conditions, such as high-speed rail, urban rail, and subway, and has extremely strong versatility. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the overall structure of the ballastless track structure according to an embodiment of this application; Figure 2 This is an exploded structural diagram of the ballastless track structure according to an embodiment of this application; Figure 3 This is a structural schematic diagram of the cast-in-place support for the ballastless track structure in the embodiments of this application; Figure 4 This is a schematic diagram of the track slab with two stiffening ribs according to an embodiment of this application; Figure 5 This is a schematic diagram of the track slab with four stiffening ribs according to an embodiment of this application; Figure 6 This is a structural schematic diagram of the prefabricated support and cast-in-place leveling layer of the ballastless track structure in the embodiments of this application; Figure 7 This is an exploded structural diagram of the prefabricated support and cast-in-place leveling layer of the ballastless track structure according to an embodiment of this application; Figure 8 This is a construction flowchart of the construction method according to Embodiment 2 of this application; Figure 9 This is a construction flowchart of the construction method of Embodiment 3 of this application.

[0024] Figure label: 1. Rail; 2. Fastener; 3. Precast track slab; 3-1. Limiting hole; 3-2. Observation hole; 3-3. Stiffening rib; 3-4. Rail support platform; 4. Cast-in-place support; 4-1. Slab bottom pad; 4-2. Longitudinal stop; 4-3. Limiting boss; 5. Observation hole cover plate; 6. Limiting hole elastic buffer pad; 7. Slab end elastic buffer pad; 8. Slab bottom elastic pad; 9. Substructure; 10. Precast support; 10-1. Grouting hole; 11. Cast-in-place leveling layer. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0026] It should be noted that in the description of this invention, the term "longitudinal" refers to the direction of extension of the track line, i.e., the direction of train travel; "lateral" refers to the direction perpendicular to the longitudinal direction in the horizontal plane; and "vertical" refers to the vertical direction. The term "slab end" refers to the longitudinal end of the track slab.

[0027] Example 1: Reference Figures 1-5 This application discloses a beam-type adjustable ballastless track structure, which includes a precast track slab 3, a cast-in-place support 4, and a three-way elastic buffer assembly.

[0028] The upper surface of the precast track slab 3 is provided with stiffening ribs 3-3 extending longitudinally, and the two longitudinal ends of the precast track slab 3 are provided with limiting holes 3-1.

[0029] The support is located between two adjacent precast track slabs 3 and includes a bottom pad 4-1 for supporting the bottom surface of the end of the precast track slab 3, a limiting boss 4-3 protruding upward into the limiting hole 3-1, and a longitudinal baffle 4-2 located between the longitudinal end faces of the two adjacent precast track slabs 3.

[0030] The three-way elastic buffer assembly includes a limiting hole elastic buffer pad 6, a plate end elastic buffer pad 7, and a plate bottom elastic pad 8, which are respectively arranged at different contact interfaces between the precast track slab 3 and the support to physically isolate the concrete entity of the precast track slab 3 from the support.

[0031] Therefore, by setting supports at the bottom of both ends of the precast track slab 3, a beam structure is formed. An elastic buffer pad or height adjustment pad is set on the support to realize the height adjustment of the track structure. The support plays the role of supporting and adjusting the geometric position of the track structure. The upper surface of the precast track slab 3 is provided with stiffening ribs 3-3 to prevent train derailment and increase the load-bearing capacity of the precast track slab 3. Limiting holes 3-1 are set at the middle position of both ends of the precast track slab 3, and matching limiting bosses 4-3 are used to limit the longitudinal and transverse movement of the precast track slab 3. The support can be connected to the lower foundation 9 through connecting steel bars to form a stable force transmission system from the precast track slab 3 to the support to the lower foundation 9.

[0032] Furthermore, in this structure, the train's running load can be transmitted step by step along a clear force transmission path. Specifically, the vertical load is transmitted from the rail 1 to the precast track slab 3 via the fastener 2, and then from the elastic pads 8 at both ends of the precast track slab 3 to the bottom pad layer 4-1 of the support, and finally into the lower foundation 9. The longitudinal and lateral loads are transmitted from the precast track slab 3 to the vicinity of the limiting hole 3-1 and the slab end area, and then from the elastic buffer pad layer 6 of the limiting hole, the limiting boss 4-3, the elastic buffer pad layer 7 at the slab end, and the longitudinal baffle 4-2 to the support, and continue to be transmitted to the lower foundation 9 through the anchoring structure between the support and the lower foundation 9. This force logic is controllable and has no redundant force transmission links.

[0033] The precast track slab 3 is preferably a reinforced concrete component precast in a factory, and can be a prestressed structure or a non-prestressed structure. Preferably, when a prestressed structure is used, the concrete strength grade can be C60; when a non-prestressed structure is used, the concrete strength grade can be C50.

[0034] Reference Figure 1 and Figure 2 The upper surface of the precast track slab 3 can be integrally formed with multiple rail support platforms 3-4, which are arranged longitudinally at intervals. Each rail support platform 3-4 has an embedded insulating sleeve for fastener 2 to match the bolt installation of the fastener 2. The fastener 2 can be a type of fastener that matches the track structure. In this example, the fastener 2 is a single-toe elastic fastener, the rail 1 is a 60kg / m rail, and the precast track slab 3 is 2300mm wide, 240mm thick, and 3370mm long.

[0035] With this configuration, the rail 1 can be reliably installed on the rail support platform 3-4 via the fastener 2, which also facilitates the one-time molding of the precast track slab 3 in the factory, improving the consistency of component dimensions. In particular, lifting sleeves can be pre-embedded on both sides of the precast track slab 3 to provide interfaces for the lifting, installation, and fine-tuning of the precast track slab 3.

[0036] It is particularly important to emphasize that the stiffening ribs 3-3 are installed along the entire length of the precast track slab 3, and there can be two or four ribs. Multiple stiffening ribs 3-3 can be arranged on one side of the track support 3-4, or they can be arranged on both sides of the track support 3-4 laterally. If two stiffening ribs 3-3 are to be installed, please refer to [the relevant section]. Figure 4 If four stiffening ribs 3-3 are provided, please refer to [the relevant documentation]. Figure 5 For example, the stiffening rib 3-3 is 250mm high and has two thicknesses: 140mm and 240mm.

[0037] It is important to emphasize that, on the one hand, stiffening rib 3-3 can significantly improve the bending stiffness and load-bearing capacity of the precast track slab section 3, perfectly matching the beam-type force system with simply supported ends, providing core mechanical protection for the realization of the beam structure, and meeting the stress requirements of train dynamic loads without requiring full support at the bottom of the slab. On the other hand, stiffening rib 3-3 simultaneously integrates the train anti-derailment guard function, replacing the guard components that traditional tracks require additional installation, eliminating the need for separate guard rail installation, and greatly simplifying the track structure; at the same time, it avoids the occupation of track clearance by additional guard rails, perfectly adapting to the stringent clearance conditions of small-radius shield tunnels in urban rail transit.

[0038] In some embodiments, refer to Figure 2 , Figure 3 and Figure 4Limiting holes 3-1 are provided at the center of both longitudinal ends of the precast track slab 3, preferably located at the center of the width direction of the precast track slab 3. The shape of the limiting hole 3-1 can be semi-circular, rectangular, or rectangular with chamfers; in a preferred embodiment, a rectangular structure with chamfers is used. For example, the rectangular structure is 300mm wide, 450mm long, and has a chamfer radius of 100mm. The limiting holes 3-1 are provided to cooperate with the limiting bosses 4-3 on the support to achieve lateral limiting and to reserve space for interface adjustment.

[0039] Furthermore, the inner wall of the limiting hole 3-1 is provided with a limiting hole elastic buffer pad 6. This limiting hole elastic buffer pad 6 can be installed by on-site bonding or by factory prefabrication and pre-application. Preferably, the limiting hole elastic buffer pad 6 has an array of anchoring ribs (not shown in the figure) distributed on the side facing the precast track slab 3. The anchoring ribs extend into the concrete during the manufacturing of the precast track slab 3 and are integrally formed with the precast track slab 3. With this arrangement, on the one hand, elastic buffering and gap adjustment can be provided at the limiting interface, and on the other hand, it helps to reduce the occurrence of gaps, slippage or detachment of the pad layer from the main body under long-term load and environmental effects.

[0040] The end elastic buffer pad 7 is arranged in the longitudinal end area of ​​the precast track slab 3. After two adjacent precast track slabs 3 are spliced ​​and installed, the end elastic buffer pad 7 is located within the buffer limiting interface range between the adjacent ends of the slabs and cooperates with the longitudinal baffle 4-2. The bottom elastic pad 8 is arranged between the bottom surface of the end of the precast track slab 3 and the area corresponding to the bottom pad 4-1. Preferably, the end elastic buffer pad 7 and the bottom elastic pad 8 adopt the same or similar setting concept as the limiting hole elastic buffer pad 6, which can be set on site or integrally formed with the precast track slab 3 in the factory stage through anchoring ribs. In this way, the limiting hole elastic buffer pad 6, the end elastic buffer pad 7, and the bottom elastic pad 8 can jointly form a three-way elastic buffer assembly, which respectively undertakes the functions of isolation, buffering, and adjustment at different interfaces.

[0041] It should be understood that the function of the three-dimensional elastic buffer component is not limited to reducing interface impact. Furthermore, this component prevents large-area direct concrete contact between the precast track slab 3 and the support, avoiding a "hard-on-hard" phenomenon and preventing direct impact, wear, and stress concentration between concrete components under train dynamic loads. This addresses high-frequency durability issues such as damage to the limiting boss 4-3 and gaps at the bottom of the slab in traditional ballastless tracks, improving the overall durability of the track structure. Moreover, when foundation settlement, arching, or other deformations occur, the geometry of the track structure can be adjusted at the corresponding interfaces by adding or replacing pads of different thicknesses. Thus, structural adjustments no longer rely solely on small-scale height adjustments of the fastener 2, but can be performed at multiple interfaces between the precast track slab 3 and the support, thereby improving the track structure's adaptability to complex foundation conditions.

[0042] In addition, for ease of construction and subsequent operation and maintenance, refer to Figure 1 , Figure 2 and Figure 4 The precast track slab 3 also has a vertical observation hole 3-2 extending from the top surface to the bottom surface in the middle. For example, the observation hole 3-2 also has a 100mm chamfer, and is 350mm wide and 2000mm long. A removable observation hole cover plate 5 covers the observation hole 3-2. The observation hole cover plate 5 is connected to the precast track slab 3 via sleeves and bolts embedded in the precast track slab 3, providing an emergency passage for the railway line and facilitating daily inspections. It should be noted that during the construction phase, the observation hole 3-2 provides a vertical operating channel for the installation, adjustment, and fixing of the mold for the bottom pad layer 4-1. During subsequent operation, it can also be used to clean dirt from the bottom of the slab, while also reducing the weight of the precast track slab 3 to some extent, facilitating transportation, installation, and construction, and improving the economic efficiency of the track structure. Furthermore, the observation hole 3-2 in the slab can also mitigate the temperature gradient effect of the precast track slab 3 to some extent, optimizing the stress and deformation of the precast track slab 3 under temperature gradient loads.

[0043] Furthermore, referring to Figure 2 , Figure 3 and Figure 4The support is set between two adjacent precast track slabs 3, preferably a reinforced concrete structure, that is, the support can be a cast-in-place support 4 or a precast support 10. The bottom pad layer 4-1 of the support is used to support the bottom surface of the end of the precast track slab 3, and the limiting boss 4-3 extends upward into the corresponding limiting hole 3-1; the longitudinal baffle 4-2 is located between the longitudinal end faces of two adjacent precast track slabs 3, more specifically, between the elastic buffer pad layers 7 at the end of two adjacent precast track slabs 3. Preferably, the limiting boss 4-3 and the longitudinal baffle 4-2 are perpendicular to each other and are arranged symmetrically in a cross shape on the bottom pad layer 4-1, and the three are integrally formed by one-time casting; for example, the longitudinal baffle 4-2 can be 180mm thick and 2300mm wide. With this configuration, the bottom pad 4-1 provides vertical support, the limiting boss 4-3 provides lateral limiting, and the longitudinal baffle 4-2 provides longitudinal limiting. The integrated structure helps reduce the splicing interface inside the support 4, thereby improving the overall rigidity and installation stability.

[0044] In some embodiments, the shape of the limiting boss 4-3 matches the limiting hole 3-1, and the height of the limiting boss 4-3 is basically flush with the upper surface of the precast track slab 3. The plane range of the bottom pad layer 4-1 corresponds to the setting area of ​​the bottom elastic pad 8 of the precast track slab 3, so as to form a local support interface. Unlike the full support of the bottom of the traditional ballastless track structure, the precast track slab 3 of this application is partially supported by the bottom pad layers 4-1 at both ends, forming a beam-type force system. The stiffening ribs 3-3 set on the upper surface of the precast track slab 3 ensure the overall bending bearing capacity of the precast track slab 3. This beam-type force system greatly reduces the amount of cast-in-place concrete poured at the bottom of the slab. Preferably, the elevation of the bottom pad layer 4-1 can also be set according to the needs of curved sections to achieve superelevation of the track.

[0045] Furthermore, a reinforcing cage can be embedded inside the support, and connecting bars or portal reinforcement bars are provided at the bottom of the support. These connecting bars, portal reinforcement bars, or truss reinforcement bars are anchored to the lower foundation 9. Specifically, the connecting bars can be pre-embedded during the construction of the lower foundation 9 or drilled and implanted into the existing foundation; the portal reinforcement bars can be selected according to the stress and reinforcement layout requirements of the support. In this way, the support can form a stable anchorage relationship with the lower foundation 9 and provide a reliable transmission path for longitudinal, lateral, and vertical loads.

[0046] In some embodiments, the support is selected as a cast-in-place support 4, which can be cast in place on the construction site after the precast track slab 3 is installed.

[0047] In other embodiments, to further reduce the amount of concrete poured on site and improve construction efficiency and quality, the support is selected as a precast support 10. The difference from the cast-in-place support 4 is that a cast-in-place leveling layer 11 is also provided between the precast support 10 and the lower foundation 9. The cast-in-place leveling layer 11 can be cast with self-compacting concrete or high-strength mortar and plays a connecting and leveling role. In this embodiment, the cast-in-place leveling layer 11 is preferably high-strength mortar.

[0048] Specifically, the precast support 10 has multiple grouting holes 10-1 penetrating the bottom pad 4-1 for casting the in-situ leveling layer 11. At least one of the grouting holes 10-1 is used for grouting, and the other at least one is used for venting and construction observation, ensuring that the leveling layer under the bottom pad 4-1 is densely grouted. The grouting holes 10-1 can be rectangular, circular, or fan-shaped, preferably a quarter-circular fan shape. Furthermore, the grouting holes 10-1 can be located in any area of ​​the bottom pad 4-1, preferably four holes located at the four corners.

[0049] For example, the bottom pad 4-1 of the precast support 10 has four grouting holes 10-1 at its four corners. Two of the grouting holes 10-1 are arranged diagonally for construction grouting, and the other two grouting holes 10-1 are arranged diagonally for construction observation and venting. The shape of the grouting hole 10-1 is a 1 / 4 circular fan shape with the arc apex facing the middle of the precast support 10.

[0050] Therefore, in the later operation and maintenance phase, the beam-type adjustable ballastless track structure of this application can exhibit significant advantages.

[0051] For example, when the lower foundation 9 experiences settlement, arching, or lateral displacement, requiring adjustments to the geometry of the track structure, the precast track slab 3 and its supports are completely physically isolated and decoupled through a three-dimensional elastic buffer assembly. Maintenance personnel do not need to remove any concrete main structure. Simply by adding extra shims or replacing them with shims of different thicknesses at the corresponding deformed locations, such as the elastic buffer pad 6 at the limiting hole, the elastic buffer pad 7 at the slab end, or the elastic pad 8 at the bottom of the slab, the geometry of the precast track slab 3 in the longitudinal, transverse, and vertical directions can be independently adjusted to restore it to its designed position. This method is simple and quick to operate, has a wide adjustment range, and is highly adaptable to deformations of the lower foundation 9.

[0052] For example, when individual precast track slabs 3 develop irreparable defects and need to be replaced, the original lower foundation 9 and supports are left undamaged. Only the old precast track slab 3 to be replaced is lifted and removed as a whole. Next, a new precast track slab 3, pre-molded in the factory with a three-way elastic buffer assembly, is hoisted and positioned above the original support. Finally, resin-based filler material is poured between the contact interface of the support and the three-way elastic buffer assembly of the new precast track slab 3, or a shim of matching thickness is inserted, ensuring a precise and secure fit between the new precast track slab 3 and the original support. The entire replacement process requires no chiseling work and can be quickly completed within railway operation windows, significantly reducing maintenance disruptions to line operations.

[0053] Alternatively, when the line needs to be upgraded for vibration reduction and noise reduction, under the premise of keeping the main form of the track structure completely unchanged, it is only necessary to replace the elastic pad at the bottom of the precast track slab 3 with a vibration reduction pad with higher vibration reduction performance, so as to quickly realize the upgrade of the line for vibration reduction and noise reduction. The solution has extremely strong versatility and scalability.

[0054] Example 2: This application discloses a construction method for a beam-type adjustable ballastless track, based on the aforementioned beam-type adjustable ballastless track structure, and employs the following technical solution: A construction method for a beam-type adjustable ballastless track, referring to Figure 1 , Figure 2 and Figure 8 The support is constructed using a cast-in-place process, and the specific construction method includes the following steps: S1. Pre-embed or implant connecting steel bars at the positions corresponding to the supports in the lower foundation 9. The lower foundation 9 can be a bridge, tunnel, etc.

[0055] S2. Arrange the support reinforcement cage at the support location.

[0056] S3. Transport the prefabricated track slab 3, which is integrally formed with three-way elastic buffer components, to the site, roughly lay and position it on the lower foundation 9, and use temporary support devices such as wooden blocks to initially position the prefabricated track slab 3.

[0057] S4. Use the lifting sleeves on both sides of the precast track slab 3 to install fine-tuning tools to fine-tune and fix the precast track slab 3.

[0058] S5. Install a support mold between two adjacent precast track slabs 3. The support mold includes a slab transverse mold and a slab bottom pad 4-1 mold. The slab bottom pad 4-1 mold is installed and adjusted through the observation hole 3-2 in the middle of the precast track slab 3, and then the support steel cage is placed in the support mold.

[0059] S6. Concrete is poured into the support mold in one go after positioning, so that the bottom pad 4-1, the limiting boss 4-3 and the longitudinal retaining platform 4-2 are integrated with the support reinforcement cage to form the cast-in-place support 4.

[0060] S7. Curing the cast-in-place support 4 until the strength meets the requirements, then removing the formwork. Finally, installing the rail 1 and fastener 2 on the track slab 3, measuring the track structure, and completing the laying of the track structure.

[0061] In the ballastless track construction method proposed in this application, the precast track slab 3 is isolated from the cast-in-place support 4 through the elastic buffer pad 7 at the end of the slab, the elastic pad 8 at the bottom of the slab, and the elastic buffer pad 6 with the limiting hole, and is decoupled from the lower foundation 9, which makes it more flexible in application during later operation.

[0062] Moreover, this simplified construction method of "factory-prefabricated integrated track slabs adapted to beam-type adjustable ballastless tracks + on-site fine-tuning and positioning + integrated cast-in-place supports" solves the problems of complex construction procedures, large on-site pouring volume, difficulty in precision control, complex installation of pressure bars, and long construction cycle of traditional ballastless track construction. The prefabricated track slab 3 completes the prefabrication of all components in the factory, and simultaneously completes the integrated installation of the track support platform 3-4, lifting sleeve, fastener 2 insulating sleeve, and three-way elastic buffer component, ensuring the processing accuracy and quality stability of components from the source and avoiding the common quality problems of on-site pasting of the pad layer; the concrete is poured in one go, and the bottom pad layer 4-1, limiting boss 4-3, and longitudinal retaining platform 4-2 of the cast-in-place support 4 are integrated and formed, without the need for separate pouring and multiple curing, which greatly shortens the on-site construction cycle; the entire process is extremely simplified, and the on-site construction efficiency is greatly improved.

[0063] In some embodiments, when the lower foundation 9 deforms and the geometry of the track structure needs to be restored, the physical isolation interface between the precast track slab 3 and the cast-in-place support 4 can be used to insert the elastic buffer pad 6 at the limiting hole, the elastic buffer pad 7 at the end of the slab, or the elastic pad 8 at the bottom of the slab, or to replace the pad with a pad of different thicknesses, so as to adjust the geometry of the precast track slab 3 in the longitudinal, transverse, and vertical directions. This does not require damaging any main concrete structure, has high efficiency, low engineering cost, and minimal impact on line operation.

[0064] In other embodiments, when it is necessary to replace the precast track slab 3, the original lower foundation 9 and cast-in-place support 4 can be kept intact. The old precast track slab 3 is first lifted and removed as a whole, and then the new precast track slab 3 is hoisted above the original cast-in-place support 4. There is no need to remove the cast-in-place support 4. By replacing the elastic buffer pad 7 at the end of the slab, the elastic pad 8 at the bottom of the slab, and the elastic buffer pad 6 of the limiting hole with different sizes and specifications, or by using cast-in-place resin materials, the replacement precast track slab 3 can be made to fit tightly with the cast-in-place support 4, thus realizing the replacement and installation of the precast track slab 3. The operation and maintenance are convenient and quick, and the slab replacement operation can be completed quickly within the railway operation window. This completely solves the industry pain points of traditional ballastless track slab replacement, which requires large-area chiseling, long track closure time, and large amount of engineering work.

[0065] In addition, when the track needs to be upgraded for vibration reduction and noise reduction, the elastic pad 8 at the bottom of the track can be replaced with a vibration reduction pad, which can achieve the upgrade for vibration reduction and noise reduction while ensuring the uniformity of the track structure.

[0066] Example 3: This application discloses a construction method for a beam-type adjustable ballastless track, which differs from Embodiment 2 in that its supports are prefabricated.

[0067] A construction method for a beam-type adjustable ballastless track, referring to Figure 1 , Figure 6 and Figure 9 This includes the following steps: S1. Pre-embed or implant connecting steel bars at the positions corresponding to the supports in the lower foundation; S2. Precast supports are selected, and the precast supports manufactured in the factory are transported to the construction site for rough laying, layout, fine adjustment and fixing; S3. Install and fix the leveling layer mold between the precast support and the lower foundation; S4. Self-compacting concrete or high-strength mortar is injected through the grouting holes set on the bottom pad of the precast support to ensure that the cast-in-place leveling layer is densely grouted. S5. Curing of the cast-in-place leveling layer; demolding after the strength meets the requirements. S6. Transport the prefabricated track slabs with three-way elastic buffer components that are integrally formed at the factory to the construction site, and perform fine-tuning and installation directly on the prefabricated supports that have been constructed. S7. Finally, install the rails and fasteners on the track slab, measure the track structure, and complete the track structure laying.

[0068] Compared with the construction method of cast-in-place bearings, the bearings in this embodiment are constructed using a prefabrication process. In addition to having all the beneficial effects of the cast-in-place bearing scheme 4, it can further reduce the amount of concrete poured on site, thereby improving construction efficiency and quality.

[0069] Therefore, this precast support 10 scheme separates the working surfaces of the support and the precast track slab 3, forming a parallel construction mode of "factory precast support and track slab + on-site precise installation". This not only further reduces the amount of on-site wet work and shortens the on-site construction cycle, but also makes the quality of the factory-produced precast support 10 easier to control and more precise, thus improving the overall construction quality and efficiency of the track structure. This scheme, together with the cast-in-place support 4 scheme in Example 2, constitutes a complete product family and construction method system for beam-type adjustable ballastless track structures, which can be flexibly selected according to the specific working conditions, schedule requirements, and resource allocation of the project site.

[0070] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A beam-type adjustable ballastless track structure, characterized in that, include: The precast track slab has stiffening ribs extending longitudinally along its upper surface, and limiting holes are provided at both longitudinal ends of the precast track slab. The support, located between two adjacent precast track slabs, includes a bottom pad for supporting the bottom surface of the end of the precast track slab, a limiting boss protruding upward into the limiting hole, and a longitudinal stop located between the longitudinal end faces of the two adjacent precast track slabs; and A three-dimensional resilient buffer assembly includes components for physically isolating the concrete body of the precast track slab from the support: The elastic buffer pad for the limiting hole is located at the interface between the precast track slab and the limiting boss. An elastic buffer pad layer is provided between the ends of two adjacent precast track slabs; An elastic pad is placed between the precast track slab and the bottom pad layer.

2. The beam-type adjustable ballastless track structure according to claim 1, characterized in that, The limiting protrusion and the longitudinal baffle intersect each other perpendicularly and are arranged symmetrically in a cross shape on the bottom pad of the plate. All three are integrally cast reinforced concrete structures.

3. The beam-type adjustable ballastless track structure according to claim 1, characterized in that, The limiting hole elastic buffer pad layer, the plate end elastic buffer pad layer and the plate bottom elastic pad are all provided with anchoring ribs on the side facing the precast track plate, and the anchoring ribs are integrally formed on the precast track plate.

4. The beam-type adjustable ballastless track structure according to claim 1, characterized in that, The precast track slab is provided with an observation hole that extends vertically from its upper surface to its bottom surface. The observation hole is covered by a detachable observation hole cover plate, which is connected to the precast track slab through a sleeve and bolts embedded in the precast track slab.

5. The beam-type adjustable ballastless track structure according to claim 1, characterized in that, The upper surface of the precast track slab is also provided with rail support platforms arranged longitudinally at intervals, and fastener insulating sleeves are pre-embedded in the rail support platforms. The number of stiffening ribs is two or four, and the multiple stiffening ribs are arranged in parallel on one side or both sides of the rail support platform.

6. The beam-type adjustable ballastless track structure according to claim 1, characterized in that, The limiting hole is located at the center of the width of the prefabricated track slab, and the shape of the limiting hole is a rectangle with chamfers; Lifting sleeves are pre-embedded along the transverse sides of the precast track slab.

7. A beam-type adjustable ballastless track structure according to any one of claims 1-6, characterized in that, The support is equipped with a support reinforcement cage, and the bottom of the support is provided with connecting reinforcement bars or portal reinforcement bars. The support is anchored to the lower foundation through the connecting reinforcement bars or portal reinforcement bars.

8. The beam-type adjustable ballastless track structure according to claim 7, characterized in that, The support is a cast-in-place support formed by on-site casting; Alternatively, the support may be a prefabricated support manufactured in a factory, and the beam-type adjustable ballastless track structure may also include a cast-in-place leveling layer disposed between the prefabricated support and the lower foundation.

9. A beam-type adjustable ballastless track structure according to claim 8, characterized in that, The precast support has multiple grouting holes through the bottom slab pad for pouring the cast-in-place leveling layer.

10. A construction method for a beam-type adjustable ballastless track structure as described in any one of claims 1-7, characterized in that, Includes the following steps: S1. Pre-embed or implant connecting steel bars at the positions corresponding to the supports in the lower foundation; S2. Arrange the support reinforcement cage at the support location; S3. Transport the prefabricated track slab, which is integrally molded with the three-way elastic buffer components, to the site and perform rough laying and positioning on the underlying foundation; S4. Use the lifting sleeves on both sides of the precast track slab to install fine-tuning tools to fine-tune and fix the precast track slab; S5. Install a support mold between two adjacent precast track slabs. The support mold includes a slab transverse mold and a slab bottom pad mold. The slab bottom pad mold is installed and adjusted vertically downward through the observation hole in the middle of the precast track slab, and then a support steel cage is placed in the support mold. S6. Concrete is poured into the support mold in one go after positioning, so that the bottom pad layer of the slab, the limiting boss and the longitudinal baffle are integrally formed with the support reinforcement cage to form a cast-in-place support; S7. Maintain and remove the support molds to complete the track structure laying.

11. A construction method for a beam-type adjustable ballastless track structure as described in any one of claims 1-9, characterized in that, Includes the following steps: S1. Pre-embed or implant connecting steel bars at the positions corresponding to the supports in the lower foundation; S2. Precast supports are selected, and the precast supports manufactured in the factory are transported to the construction site for rough laying, layout, fine adjustment and fixing; S3. Install and fix the leveling layer mold between the precast support and the lower foundation; S4. Self-compacting concrete or high-strength mortar is injected through the grouting holes set on the bottom pad of the precast support to ensure that the cast-in-place leveling layer is densely grouted. S5. Curing of the cast-in-place leveling layer; demolding after the strength meets the requirements. S6. Transport the prefabricated track slab, which is integrally formed with the three-way elastic buffer component, to the construction site and perform fine-tuning and installation directly on the prefabricated support that has been constructed. S7. Finally, install the rails and fasteners on the track slab, measure the track structure, and complete the track structure laying.

12. A construction method for a beam-type adjustable ballastless track structure as described in any one of claims 1-9, characterized in that, When it is necessary to replace the prefabricated track slab, the following steps are included: Keep the original lower foundation and the aforementioned supports intact, and lift and remove the old precast track slab to be replaced as a whole. The new prefabricated track slab, which is integrally formed with the aforementioned three-way elastic buffer components, is hoisted and positioned above the original support; By casting resin material or inserting a pad of matching thickness between the contact interface of the support and the three-way elastic buffer component of the new precast track slab, the new precast track slab and the support are tightly and firmly connected.

13. The construction method of a beam-type adjustable ballastless track structure according to claim 12, characterized in that, When the lower foundation deforms and the track structure needs adjustment: By utilizing the physical isolation between the precast track slab and the support, the geometric position of the precast track slab in the longitudinal, transverse and vertical directions can be independently adjusted by adding or replacing pads of different thicknesses at the locations of the elastic buffer pads at the limiting holes, the elastic buffer pads at the ends of the slabs, or the elastic pads at the bottom of the slabs.

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